Estimation of Equivalent Seismic Amplification Factor of Mountain Slopes on Inclined Bedrock

Abstract

Recent earthquakes such as Gyeongju earthquake has occurred frequently in Korea. It is very important to predict the collapse of the slope by earthquake, because serious economic and damage of human life may occur. A pseudo-static analysis method based on the limit equilibrium is generally used to evaluate of the slopes stability during earthquakes. However, the slope failure surface using pseudo-static method has limitations that could not consider slope dynamic response and seismic wave characteristics during earthquake. Therefore, in this study, two-dimensional nonlinear dynamic analyses were performed, and the failure surface of mountain slope was decided through the analysis of slope’s dynamic response characteristics. And the amplification factor according to slope failure surface changes was calculated using the equivalent acceleration concept. It is very important that determination of the failure surface. First, it affects the calculation that equivalent acceleration and yield acceleration. Second, Amplification factors could be changed by failure surface determination. As a result of this research review, it was confirmed that the failure surface could change according to the seismic wave characteristics. Also, the calculated amplification factors differed according to the changes in failure surface. Therefore, new regression equations are proposed by analyzing the factors affecting amplification. The amplification factor calculated by the new equation is more accurate than the amplification factor calculated by the conventional equation.